Kai Xu, in a letter to the U.S. District Judge John Corbett O'Meara, said he sold turtles to fund his college degree, the Associated Press reported. He is an engineering student, one semester short of graduating from the University of Waterloo in Ontario, Canada.

According to Reuters, for almost six months in 2014, the 27-year-old admitted to smuggling or trying to smuggle more than 1,600 turtles of different breeds from the United States to Canada.

Xu was first detected in August of 2014, when he crossed the U.S.-Canada border into Detroit. American Agents watched him pick up a package at a parcel center, and head back to Canada, where he was stopped by the Canadian Border Services.

Canadian officials then discovered 51 live turtles inside Xu's sweatpants -- 41 taped to his legs, and 10 more hidden between his legs, Reuters reported.

The Detroit News reported that officials speculated the man was trying to ship the turtles to China, where they will be sold as pets or food. Court documents stated that Xu was accompanied by another Chinese-Canadian man, who was arrested when he attempted to fly to Shanghai with more than 200 turtles in his luggage.

Even though it is not illegal to buy turtles from U.S. breeders, the Associated Press reported that shipping overseas without a federal permit is a crime.

According to the Detroit News, the Eastern box turtle, just one of the turtle species that was found inside Xu's pants, is worth at least $800.

He has since been held in custody for the last 19-months, until his recent sentencing.

Xu was finally sentenced to 57 months in prison. Even though his attorney, Matthew Borgula argued that his operation was not sophisticated, the sentencing was enhanced due to the value of the turtles. According to the Associated Press, the shipments that were intercepted at the border were estimated to be worth over $1 million.